Detachable-blade knife



Sept. 3, 1940. 1-5511 DETACHABLE-BLADE KNIFE Filed May 1. 1939 INVENTOR Patented Sept. 3, 1940 r Nicholas Testi, Boston, Mass, assignor to Gillette Safety Razor Company, Boston, Mass, a corp'oration of Delaware Application May 1, 1939, Serial No. 271,115

4Claims. (01. so -156) This invention relates to knives of general utility designed to I employ replaceable safety razor blades as their cutting elements.

- In generalthe objects of the invention are to provide at low cost a'thin flat knife convenient to be carriedin the'pocket of the user and having a handle shaped to support the blade firmly in exposed cutting position or securely in completely guarded position, still permitting the convenient removal of the blade for replacement Whenever desired. I p To these ends an important feature of the invention consists in a perforated handle in combination with a spring clip having arms for engaging opposite sides of'the handle. One arm of the clip is equipped with a' fulcrum pin shaped to engage the blade through the perforation of the handle and the other arm shaped to cooperate with the handle as a retainerfor the knife as a whole. Means are provided between the handle and the clip for positively holding the clip from slipping off the handle while permitting suflicient' movement thereof to disengage the blade. For example, as herein shown the clip is connected't'o the handle by a pin which positively engages the clipwith: a clearance sufficient .to permit the fulcrum pin to be retracted and moved out of registration with the perforation in the handle of the knife. When the clip is so positioned the blade maybe freely withdrawn or replaced and when once replaced the clip may be restored to its operative position inwhich the fulcrum pin enters thehandle and passes through a suitable perforation in the blade. The fulcrum pin not only co-operates to support the blade firmly in cutting position but serves as an axis about which it may be swung for movement into and out of guarded position.

These and'other features of the invention will be best understood and appreciated from the following description of two preferredembodiments thereof selected for purposes of illustration and shown in the accompanying drawing, in which:

Fig. l-is a view in elevation of a complete knife exemplifying one embodiment of the invention;

Fig. 2 is a fragmentary view of the same knife showing the blade moved partially to its guarded position;

Fig. 3 is a view in perspective of the handle or holder; 1 1

Fig-4 is a view in perspective of the clip member;

Fig. 5 is a plan view of a blade of one type u b e f e.1 t e kn e;, I

Fig. 6 Ba view in elevation of a knife exemplifying another embodiment of the invention;

Fig. 7 is a similar view of the same knife with its blade in guarded position; and

Fig. 8 is a view on a smaller scale of the same A knife showing the clip in blade disengaging position.

The handle or holder Ill of the knife shown in Figs. 1 and 2 comprises a sheet metal blank folded upon a longitudinal axis and is of awidth when folded-slightly greater than that of the blade it'is to contain. The blank may be provided with an embossed area II of ornamental contour which is effective not only to stiffenthe handle but to provide clearance for the corner of the blade as the latter isswung from cutting to guarded position as will presently appear. The handle is provided in its free'edge with an elongated recess1l2 in which the cutting edge of the blade is exposed. It is. also provided, as best shown in Fig. 3, with a fulcrum pin hole l3 disposed approximately centrally in the handle and extending through both of its sides. I In line with this hole and near one end the holder is provided on one face with'a pair of short project? ing pins l l; and I; At the inner end of the blade-exposing recess l2 the walls of the handle are slightly flared to facilitate the introduction of the endof a blade between the two side walls of the-handle. Thehandle may be constructed of sheet steel or other metal which is resilient so thatits two side walls may be made. normally to engage each other or an interposedblade as th casemaybe. i i

Co-operating with the handle I0 is a separate detachable-forked clip having a fiat body portion 20 and an .oppositely. disposed tongue 2!. The clip is also ofresilient metal and the tongue 2| is normally; engagedwith the body portion thereof. The body portionZU is provided at its outer end with a fulcrum pin 22.of such diameter as completely tofill the fulcrum pin hole I3 of the handle and of such-length asto extend entirely through bothv sides of thehandle. The body of the clip is also provided with a pair of spaced holes-23.and 24 and is connected to the tongue ,by a perforated loop which clears the end. of the handlev when the clip is assembled thereonas shown in Figs. 1 and 2. The hole 24 in the clip is shaped and located to fit over the pin 14 of the -handle. -The hole 23 is of substantially larger diameter and is located in position to receive the pin l5 of the handle with substantial clearance... The arrangement is such that when the outer or free end of the-body 20, of-the clip is sprung outwardly sufliciently to disengage the fulcrum pin 22 from the hole I 3 in the handle the clip may be then swung to one side or the other about the pin 14 as an axis sufliciently to carry the fulcrum pin 22 out of line with the hole l3, thus leaving the interior of the handle clear for the presentation or removal of the blade while the fulcrum pin 22 is yieldingly pressed against the side face of the handle.

The handle is adapted to receive any form of blade having a perforation located near one end in conventional relation to its cutting edge. A suitable blade 18 of the Gillette double-edged type is shown in Fig. 5. This is provided with a centrally disposed elongated perforation having enlargements l9 at each end which thus supply the necessary perforations to receive the fulcrum pin 22. When the clip has been displaced to hold the fulcrum pin 22 in an inoperative position the blade l8 may be presented endwise between the flaring portions I6 of the handle and advanced until one of the enlargements l9 registers with the hole l3 of the handle. Then the clip may be rocked transversely and the fulcrum pin 22 permitted to snap into place, whereupon the blade becomes pivotally connected to the handle. The blade may now be swung about the fulcrum pin 22 into cutting position as shown in Fig. 1 wherein one edge rests against and is supported by the fold vertex of the handle and the other edg is exposed for cutting in the recess l2; or the blade may be swung in clockwise direction about the fulcrum pin 22 as suggested in Fig. 2 into a completely guarded position in which the entire cutting edge of the blade lies to the left of the recess l2 being held yieldingly in this position by engagement of the sides of the handle. In its guarded position the unsharpened end portion of the blade extends slightly beyond the end of the handle Ill. The user may consequently safely engage this unsharpened portion of the blade when he desires to swing it again into cutting position.

It will be seen that I have provided a detachable blade knife of three component parts, each adapted for production under favorable manufacturing conditions, and all adapted to be readily assembled. The clip 28-2l, moreover, has the double function of retaining the blade in its handle and of retaining the knife as a whole in the pocket of the user. 7

In Figs. 6-8 is illustrated, as another embodiment of the invention, a knife including a singleedge blade. In its construction the handle or holder 30 comprises a sheet metal blank folded upon a longitudinal axis and of a width when folded at least equal to that of the blade it is to contain. The blank is provided with a bulged portion 3| in its folded vertex to provide clearance for the corner of the blade as the latter is swung from cutting to guarded position. The handle is cut away to present a curved edge 32 at one end which increases the length of exposed edge when the blade occupies its operative position. The handle is also provided with a fulcrum pin hole 33 located some distance within the curved edge 32 and extending entirely through both sides of the handle. Near its other end, the handle is provided wth a short projecting pin 34 for retaining the clip, as will be presently explained, and below the pin 34 in the open edge of the holder is provided a notch 35 through which one corner of the blade may be reached when it is desired to swing the blade into its operative or cutting position. The handle is also provided at its right-hand end as shown in Figs. 6 and 7 with a perforated eye or loop 31 to which a light chain or cord may be attached if desired.

Co-operating with the handle is a detachable clip having a fiat body portion and an oppositely disposed tongue 4|. The clip is made of resilient metal and is adapted to be slipped upon the handle and to engage its opposite sides with yielding pressure. The body portion 40 is provided at its outer end with a fulcrum pin 42 of such diameter as completely to fill the fulcrum pin hole 33 in the handle and of such length as to extend entirely through both sides. The body of the clip is provided with a hole 43 arranged to receive with clearance the pin 34 of the handle and to retain the clip in place while permitting it to be rocked transversely sufficiently to disengage the fulcrum pin 42 from the hole 33 when it is desired to hold the fulcrum pin in inoperative position in detaching the blade. The clip is cut away at its fold or bend to receive the projecting eye 3'! of the handle and has sufficient clearance so that it may rock slightly upon the end of the handle when released for such movement by the withdrawal of the fulcrum pin 32 from the hole 33.

The blade 26 shown in Figs. 6-8 is of the Valet type having a single sharp edge and a fiat unsharpened rear edge. The blade is provided near one end with a circularperforation of suitable size to receive the fulcrum pin 42 of the clip. It is also provided in its end edges with recesses setting off projecting lugs 21 by which the blade may be manipulated without danger of cutting. The clip, as before, has the double function of retaining the blade in the handle and of retaining the knife as a whole in the pocket of the user.

When the blade is in operative position as shown in Fig. 6 it is held in place by the fulcrum pin 42 between the sides of the handle 30 and with its rear unsharpened edge in contact with the fold vertex of the handle and the major part of its cutting edge exposed for cutting. The blade may be moved into guarded or inoperative position by merely swinging it in a counterclockwise direction about the fulcrum pin 42 until it occupies the position shown in Fig. 7. When it is desired to disengage the blade the forward end of the clip 40 may be easily raised sufficiently to disengage the fulcrum 42 from the hole 33 and the clip may be rocked to carry the fulcrum pin out of line with the hole and into some such position as suggested in Fig. 8. Thereupon, the blade may be drawn freely out of the handle and replaced with a new sharp blade whenever desired.

Having thus disclosed my invention and described two embodiments thereof for purposes of illustration but not in any limiting sense, I claim as new and desire to secure by Letters Patent:

1. A detachable-blade knife comprising a handle having a hole for a fulcrum pin, a spring clip having arms for engaging opposite sides of the handle, a fulcrum pin projecting from one arm, a perforated blade shaped to swing on said fulcrum pin from guarded to exposed position, and means on the handle for engaging the said arm for adjustably connecting the clip to the handle. r

2. A detachable-blade knife comprising a handle of sheet metal folded to present opposed sides which are perforated to receive a fulcrum pin, a perforated blade, and a forked removable clip having arms for engaging opposite sides of the handle and a fulcrum pin for pivotally retaining the blade between the sides of the handle with its back in contact with the fold vertex of the handle and its cutting edge exposed, the blade being pivotally movable about the fulcrum pin to concealed position in the handle.

3. A utility knife comprising a handle of sheet metal folded to present opposed sides which are perforated to receive a fulcrum pin and recessed adjacent to one end, a razor blade narrower than the handle and perforated to receive a fulcrum pin, and a forked detachable clip having a fulcrum pin for the blade, means for retaining said clip on the handle with its fulcrum pin in inoperative position to permit removal of the blade or in operative position in which the blade may be moved pivotally on the fulcrum pin from concealed to cutting position or vice-versa.

4. A utility knife comprising a thin fiat handl having a hole for a fulcrum pin, a perforated blade, a forked spring clip having arms for engaging opposite sides of the handle, one carrying a fulcrum pin and the other shaped to co-operate with the handle as a retainer for the knife as a Whole, and means for positively holding the clip from slipping off the handle While permitting limited displacement thereof.

NICHOLAS TESTI. 

